1080p LCD TV Picture Quality

by Vincent Teoh

8 March 2007

Contrast Ratio

Rank

LCD TV

Points

1

Sony KDL40W2000

3

2

Sharp LC42XD1E

2

3

Samsung LE40F71BX

1

Defined as the ratio of intensity between the brightest white and the darkest black which lends dynamic range to images, contrast ratio is probably the most important element of picture quality that determines the appeal of any display device. While shortfalls in colour accuracy and decoding require a discerning eye to spot, most people can readily tell the difference between a HDTV that's "bright" (high contrast ratio) and one that's "dull" (poor contrast ratio).

It must be stressed that contrast ratio is meaningless without knowing the conditions under which it was measured. Manufacturers tend to lower black level (labelled as "brightness" in the user menu on most HDTVs) and increase white level ("contrast") excessively to inflate contrast ratio, but this usually entails a loss in shadow and white detail making the final picture utterly intolerable.

Here at HDTVtest, we believe that the only contrast ratio worth talking about is the one measured after proper calibration is carried out to the D65 imaging standard. Using our in-house instruments, the Sony KDL40W2000 clocked in at 931:1; the Sharp LC42XD1E, 816:1; and the Samsung LE40F71BX, a disappointing 536:1.

Black Level & Shadow Detail

Rank

LCD TV

Points

1

Sharp LC42XD1E

3

2

Sony KDL40W2000

2

3

Samsung LE40F71BX

1

Black level has traditionally been the Achilles' heel of LCD TVs as a result of their invariably-active liquid crystal matrix, but this no longer holds true with the arrival of Sharp LC-42XD1E and Sony KDL40W2000U. The Sharp LC42XD1E had no problem matching the reference-level black on the Panasonic TH42PH9, although it must be pointed out that the plasma maintained a slight edge in terms of shadow detail. The Sony KDL40W2000U's otherwise commendable black level was unfortunately "clouded" by uneven backlight discolouration so it had to settle for runner-up. The black level and shadow detail on the Samsung LE40F71B was distinctly average – "murky" is probably the best word to describe it.

Colour Saturation & Accuracy

Rank

LCD TV

Points

1

Sony KDL40W2000

3

2

Sharp LC42XD1E

2

3

Samsung LE40F71BX

1

Samsung LE40F71BX's always-on DNIe processing prevented us from correcting the errors in greyscale, colour point accuracy and colour decoding even after multiple calibration runs, so it's again left to the Sharp and Sony to battle for top honours in this category. In the end Sharp's indelible red push – still noticeable however mild – drove us towards the Sony.

Detail & Sharpness

Rank

LCD TV

Points

1

Sony KDL40W2000

3

2

Samsung LE40F71BX

2

3

Sharp LC42XD1E

1

All three panels feature a native resolution of 1920 x 1080, but the Sony KDL-40W2000 secured top spot because 1:1 mapping was easily achieved through HDMI and component connections by turning on "Full Pixel". 1:1 over VGA is apparently also possible using Powerstrip (a third-party graphics card management software) but we did not have time to test this.

The Samsung LE40F71BX did 1:1 over VGA out-of-the-box, but required a firmware upgrade (using a not-so-easily-obtainable cable) before it could do the same over HDMI. The Sharp LC42XD1E could only obtain 1:1 mapping through its "Underscan" mode over HDMI.

Motion Handling

Rank

LCD TV

Points

1

Samsung LE40F71BX

2

=

Sharp LC42XD1E

2

=

Sony KDL40W2000

2

Although just a shade behind the ClearLCD-powered Philips 42PF9831D and the Panasonic TH42PH9 plasma, all three LCD TVs handled fast motion equally competently – we could have watched football or rugby comfortably on any of these sets without complaints.

Viewing Angle

Rank

LCD TV

Points

1

Samsung LE40F71BX

2.5

=

Sony KDL40W2000

2.5

3

Sharp LC42XD1E

1

The viewing angle of the KDL40W2000 and LE40F71BX (120° horizontally) were similarly impressive, which is unsurprising given that they employ the same SPVA technology. In this aspect, the LC42XD1E truly "pales" in comparison... discolouration was evident beyond 30° off-axis.

Video Processing

Rank

LCD TV

Points

1

Sony KDL40W2000

3

2

Samsung LE40F71BX

2

3

Sharp LC42XD1E

1

Viewing angle aside, this is probably the department which dented Sharp LC42XD1E's bid most severely, allowing the Sony KDL40W2000U to pull ahead. Digital noise in the form of pixel swarming was prevalent in all but the most pristine (read: immaculately transferred HD DVD or BD) of sources fed to the Sharp LC-42XD1E. The Samsung LE40F71B fared better here, but still lost out to the Sony KDL40W2000 due to inferior scaling and deinterlacing – we could still see the occasional combing creeping through on 1080i material.

Backlight Uniformity

Rank

LCD TV

Points

1

Samsung LE40F71BX

3

2

Sharp LC42XD1E

2

3

Sony KDL40W2000

1

This LCD TV fixture deserves a mention because of widespread complaints of uneven discolouration resulting from poor quality control. In our shootout, Samsung's was perfect; we decided that we could tolerate the Sharp's faint vertical "bands" (which was only really present when tested with a mid-grey pattern and did not impact on picture quality at all) more than the Sony's "clouding" that surfaced during dark scenes.